Tremor in Parkinson’s disease: cause, symptoms, treatment

Tremor is the medical term for muscle tremors. It is a symptom that can have many causes and triggers. Involuntary trembling of the hands at rest is a typical sign of Parkinson’s disease. This type of tremor is also known as resting tremor. In Parkinson’s disease, tremor can occur in different situations: When eating, when you are about to bring a spoon to your mouth or drink from a glass, write down a quick note or tie your shoes. Simple everyday routines suddenly become a challenge for those affected. As the disease progresses, it is not only the arms and hands that are affected by tremors, but also other areas of the body, such as the legs and feet, the head or even the vocal cords.

Find out all about the cardinal symptom of Parkinson’s disease here. What are the causes of tremor? What are the characteristic symptoms and which neurological examinations are used for the diagnosis? We also provide an overview of the many treatment options for Parkinson’s tremor at rest.

Tremor in Parkinson’s disease: what is it?

Tremor – the involuntary, trembling movements of muscles at rest – is probably the best-known symptom of the neurodegenerative disease Parkinson’s disease. Together with muscle stiffness (rigor) and slowness of movement (bradykinesia), tremor is one of the cardinal symptoms of Parkinson’s disease. Since the current guideline (2025), postural instability is no longer a so-called cardinal symptom, as it tends to occur at a late stage of Parkinson’s disease.

It was the English doctor and namesake James Parkinson who, in his treatise “An Essay on the Shaking Palsy”, described the disease once known as shaking palsy in detail, with all its motor symptoms and non-motor symptoms. His observations are still relevant to the diagnosis today, even though many other symptoms have since been added that the doctor did not ascribe to the disease at the time.

Resting tremor in Parkinson’s disease

In Parkinson’s disease, a so-called resting tremor occurs for the most part. This means that the tremor is noticeable when the muscles are relaxed and in a resting position. For example, the hand trembles even though it is lying very still on the table or the armrest of the chair. If a movement is now performed, the concentration on the upcoming task contributes to the tremor increasing. Attempts to suppress the tremor are also in vain. In this case, the tremor often becomes even stronger. If, on the other hand, movement begins, the tremor usually disappears again.

Different forms of tremor

Not all tremors are the same: trembling does not mean that you have Parkinson’s disease. There are many different forms of tremor, which can have very different causes. It is important to differentiate between them in order to make or confirm a diagnosis of Parkinson’s disease.

An essential tremor, for example, is also known as an action tremor because the tremor typically occurs during a conscious movement and the muscles have to fight against gravity, for example when holding an object, writing or other fine motor movements. The tremor typical of Parkinson’s, on the other hand, occurs at rest and improves when a voluntary movement is performed. In essential tremor, other symptoms of Parkinson’s disease are also missing as a distinguishing feature. The exact causes of essential tremor are still not fully understood.

The most important forms of tremor syndrome at a glance

• Physiological tremor: This slight tremor is the normal tremor that everyone exhibits to a certain degree, e.g. when stretching the hand forward. Physiological tremor can also occur with stress, lack of sleep or too much caffeine.
• Tremor at rest (Parkinson’s tremor): The tremor occurs in a physically relaxed and calm position and typically improves with active movement.
• Action tremor (essential tremor): A further distinction is made here between holding tremor (trembling when holding an arm against gravity), intention tremor (trembling during purposeful movement) and isometric tremor.
• Psychogenic tremor: The tremor manifests itself as a resting, holding or intention tremor and is caused by mental overload.
• Orthostatic tremor: This is a high-frequency tremor of the leg muscles when standing, often accompanied by a feeling of instability.
• Dystonic tremor: Trembling can occur in people with dystonia. This is a rare group of movement disorders that are associated with muscle spasms and muscle contractions.
• Holmes tremor (brain lesion): This is a resting tremor and intention tremor with a slow frequency that is visible in people with a brain lesion, e.g. due to MS (multiple sclerosis) or brain injuries.

Tremor in Parkinson’s disease: What are the causes?

If your steady hand starts to tremble, there can be many reasons behind it. Perhaps factors such as cold, anxiety or too many cups of coffee or medication are the reasons? However, a clearly visible tremor that occurs at rest is a key symptom of Parkinson’s disease. But what causes tremors in Parkinson’s?

The causes of Parkinson’s disease are made up of various factors. There is often a combination of environmental and genetic factors. However, a disturbed intestinal microbiome (intestinal flora), a misdirected immune system, inflammation of the nerve cells, medication and, last but not least, age are also possible risk factors.

Dopamine deficiency in the brain causes the symptoms

The main cause of a neurodegenerative disease is to be found in our brain. In Parkinson’s, movement disorders are caused by a disorder in a very specific area of the brain, in the black substance (substantia nigra) in our midbrain and the associated areas, the so-called basal ganglia. These are responsible for controlling and coordinating our movements.

The nerve cells that produce the messenger substance (neurotransmitter) dopamine in the black matter progressively die off in Parkinson’s disease. This results in a lack of dopamine in the body, which causes motor symptoms such as tremor, rigidity and lack of movement. This is because if the neurotransmitter dopamine is missing, the signals in the basal ganglia are processed incorrectly and the transmission of signals between nerve cells and muscles is disrupted. As a result, our movements are no longer coordinated and purposeful. Dopamine is also central to motor learning and motivational control.

If more than 50 percent of the dopaminergic nerve cells in the brain are destroyed, the cardinal symptoms of tremor, rigor and bradykinesia develop. As the disease progresses, nerve cells in other regions of the brain are also affected, which can lead to many of the accompanying symptoms of the disease, such as chronic pain, paresthesia, sleep disorders, digestive disorders and mental disorders such as depression, anxiety or Parkinson’s dementia.

Symptoms of tremor: how tremor manifests itself in Parkinson’s disease

People with Parkinson’s disease suffer from an increasing disorder of movement. Arms, hands, fingers, legs, feet, trunk and head can be affected and tremble. What exactly does Parkinson’s tremor look like? It is a rhythmic, involuntary tremor that initially only occurs in one part of the body, such as a hand or finger, when it is actually in a calm position and completely relaxed. The hand then moves back and forth evenly – sometimes up to six to nine times per second. This resting tremor is characterized by the fact that it disappears again with voluntary movement.

In many Parkinson’s sufferers, the tremor gets worse and worse over time and spreads further and further in many of those affected. At first, only one hand begins to tremble, later possibly the whole arm or foot and then the leg. As the disease progresses, the tremor, which is initially one-sided, can also spread to the other side of the body – in severe cases to the lips, vocal cords or jaw. However, this is a long, gradual process. A worsening of the tremor is also due to the fact that the medication that is actually helping can no longer develop its full effect. Such fluctuations are also referred to as a fluctuation in effect.

Internal tremor and pill-popping

Some patients move their thumb and index finger towards each other during resting tremor as if they were spinning a ball between them – this is also known as “pill spinning”.

Some people also experience an “internal tremor”. This is a feeling of trembling in the body that is imperceptible to other people. The treatment for an internal tremor is the same as for an external tremor.

Diagnosis: How tremor is diagnosed in Parkinson’s disease

There are different types of tremor, which can be caused by different diseases. The frequency of the tremor is an important criterion for differentiating between them. Resting tremor, which has a frequency of four to seven hertz (Hz), is typical of Parkinson’s disease. The unit of measurement Hertz provides information about the number of oscillations, i.e. the involuntary, rhythmic movements of a body part per second. In Parkinson’s tremor, the frequency is generally lower than in other types of tremor.

In addition, with Parkinson’s, the muscle tremors stop when those affected move. The frequency of a tremor can also be influenced by factors such as tension, stress, medication or fatigue and can fluctuate.

To determine the frequency of a tremor, neurologists first observe their Parkinson’s patients and have them perform certain activities, such as bringing a glass of water to their mouth and holding it there. An uncontrolled shaking of the hands would tend to indicate an essential tremor. Further indications are provided by technologies that can measure the electrical voltage in a muscle, such as electromyography (EMG) or accelerometry (a method of measuring movement).

Sometimes other tests and imaging procedures are also used, such as a brain scan, a so-called DaTSCAN.

The criteria of the Movement Disorder Society (MDS) form the basis for the diagnosis of Parkinson’s disease. These include

• Bradykinesia and another cardinal symptom: rigor, tremor (resting tremor).
• Unilateral onset of symptoms.
• Progressive and long-term course of the disease.
• Clear response to the drug levodopa (L-dopa).
• Long-term response to drugs with a dopamine-like effect (dopamine agonists).

Tremor in Parkinson’s disease: treatment and tips for everyday life

Important pillars of Parkinson’s therapy and muscle tremor are drug treatment, device-based therapies such as deep brain stimulation (DBS) and supportive measures such as physiotherapy, occupational therapy, speech therapy and psychotherapy. We will provide you with information on how you can bring tremors under better control.

Although there is no cure for tremor in Parkinson’s, fortunately there are many options available to you to treat the muscle tremors. Especially in the early stages of the disease, you can suppress hand tremors by, for example, holding an object in your hand that you can squeeze or move when the tremor starts.

Drug treatment to reduce the tremor

Dopaminergic therapy is intended to compensate for the lack of dopamine in the brain and alleviate Parkinson’s symptoms such as akinesia, rigor and tremor. Medications that influence dopamine levels include

1. Levodopa (L-Dopa)
2. Dopamine agonists
3. MAO inhibitors
4. COMT inhibitors
5. Anticholinergics (in severe cases)

Drug treatment for Parkinson’s requires regular monitoring by the treating neurologist. Long-term use of medication can lead to side effects that may require dosage adjustments or other measures.

Deep brain stimulation (DBS)

“Deep brain stimulation”, or DBS for short, is the English term for deep brain stimulation, which is one of the effective therapies for tremor in Parkinson’s disease. It is used as a supportive measure when medication may no longer be sufficiently effective as the disease progresses. DBS is a type of brain pacemaker that is inserted during a surgical procedure. Small electrical currents are passed through electrodes that are permanently implanted in the brain and positively influence certain areas of the brain.

MRI-guided focused ultrasound (MRgFUS)

An MRI-guided focused ultrasound directs high-frequency sound waves through the skull to very specific areas of the brain, only millimeters in size, which play a special role in tremor. Focused ultrasound is a non-invasive procedure that takes place via imaging (magnetic resonance imaging) and can significantly reduce tremor by using ultrasound to switch off the damaged brain cells under visual and temperature control in the magnetic resonance scanner. The nerve cells that trigger the muscle tremor are destroyed.

Like THS, this FUS treatment is used as a supportive measure when the medication no longer responds sufficiently and the tremor is the most prominent symptom of the disease.

Good to know: There are two locations in Germany that offer the MRgFUS therapy procedure: the University Hospital Bonn and the University Hospital Schleswig-Holstein in Kiel.

Supportive therapies for tremor

In addition to drug treatment, physiotherapy, occupational therapy and psychotherapy are important components of tremor therapy:

• Physiotherapy: With regular, specific movement exercises from physiotherapy, you can train muscle coordination, fine motor skills and muscle strength as well as improve control over movements.
• Occupational therapy: In occupational therapy, you will be taught techniques to alleviate muscle tremors. The use of aids in the home is part of this and is explained in detail by occupational therapists. They help with many everyday tasks – whether special cutlery for eating or adaptive devices that make writing or putting on and taking off clothes easier.
• Psychotherapy and self-help groups: Both can help to cope better with the diagnosis and the disease of Parkinson’s disease, to name fears and to come to terms with them. Talking to like-minded people in self-help groups and sharing helpful tips on dealing with tremor and the like are also perceived as enriching and give the feeling of not being alone with all the challenges of the disease.

Tips for everyday life: relaxation, exercise, nutrition

Important everyday adjustments that can have a positive effect on muscle tremors include relaxation methods, sport and exercise as well as a balanced diet.

Learn relaxation methods

Factors such as stress, tension and anxiety can exacerbate a tremor. Therefore, try to find ways to counteract this and bring more relaxation into your everyday life. Relaxation methods such as progressive muscle relaxation, yoga, mindfulness, meditation or even Qigong and Tai Chi from the field of Chinese medicine can be helpful companions in stressful times. Music therapy or art therapy are also suitable for relaxation.

Integrating sport and exercise into everyday life

Physical activities and exercise in everyday life have proven to be suitable not only for tremor, but also for Parkinson’s disease in general. Sport has a positive effect on the body, balance, coordination and mental well-being. Just see which sports you like. The main thing is that you enjoy it.

Table tennis and even boxing are very popular with people with Parkinson’s and help to get the tremors under control for a certain period of time. All sports with large sequences of movement and steady rhythms are particularly beneficial. These include, for example, Tai Chi, dancing or Nordic walking.

Prefer a balanced diet

To ensure that the body is supplied with all vital nutrients, doctors recommend a healthy, balanced diet for a disease such as Parkinson’s disease. Although the tremor cannot be directly improved with the right diet, the progression of the disease can. Research has shown that the Mediterranean diet in particular has proven to be a suitable form of nutrition for Parkinson’s and can alleviate and therefore positively influence the course of the disease.

The Mediterranean diet consists mainly of lots of fresh fruit and vegetables, fiber, natural oils with polyunsaturated fatty acids, fish, legumes and little meat. If possible, sufferers should avoid ready meals, saturated fatty acids and sugar.